Question

-0,8x-(0,6x-0,7у) , если 2x-y=-8 ?

Answer 1

1) x=(y-8)/2
2) -0,14(y-8)/2+0,7y = -0,7y+0,56+0,7y=0,56

Answer 2

To find the value of the expression -0.8x - (0.6x - 0.7y) when the equation 2x - y = -8 holds true, we need to substitute the value of y from the given equation into the expression.

Step 1: Solve the equation 2x - y = -8 for y: y = 2x + 8

Step 2: Substitute the value of y into the expression -0.8x - (0.6x - 0.7y): -0.8x - (0.6x - 0.7(2x + 8))

Step 3: Distribute the negative sign inside the parentheses: -0.8x - 0.6x + 1.4x + 5.6

Step 4: Combine like terms: (-0.8x - 0.6x + 1.4x) + 5.6 (0.2x) + 5.6

So, the value of the expression -0.8x - (0.6x - 0.7y) when 2x - y = -8 is: 0.2x + 5.6